10.22376/ijpbs.2019.10.1.p1-12 Volume 9 Issue 4 2018 (October - December) L-asparaginase (L-AsnA) is cosmopolitan among microorganisms and has vital applications in medical and in food technology sectors. Therefore, the power of the assembly, of L-AsnA from lessThan i greaterThan Phormidium formosum lessThan /i greaterThan was tested. Cyanobacterium lessThan i greaterThan Phormidium formosum lessThan /i greaterThan were isolated from Eastern harbor of Mediterranean Sea coast of Alexandria, Egypt. Different incubation temperatures ranged from 20°C to 45°C were applied to get the optimum incubation temperature for the enzyme production using modified F/2 medium. The pH range between pH 6.0 to 10.0 was applied on the modified F/2 production medium to demonstrate the optimum pH for L-asparaginase production. Adsorption of  lessThan i greaterThan Phormidium formosum lessThan /i greaterThan  on different solid porous supports such as pumice, coal, ceramic, luffa pulp and polyurethane foam for l-asparaginase production was investigated. lessThan i greaterThan Phormidium formosum lessThan /i greaterThan cultures were grown in F/2 medium for 14 lessThan sup greaterThan th lessThan /sup greaterThan days. The cultures of lessThan i greaterThan Phormidium formosum lessThan /i greaterThan showed a high L-AsnA enzyme activity (49.120 U/ml). the optimized pH and temperature were 8 and 30 lessThan sup greaterThan o lessThan /sup greaterThan C, respectively. Immobilization using adsorbed Luffa pulp enhanced the enzyme production compared to the conventional free- cells repeated reuse of the adsorbed cells and achieved the maximum enzyme specific activity (52.562U/ml). Scans using electron microscopic showed the adsorption of lessThan i greaterThan P. formosum lessThan /i greaterThan on the pores of luffa pulp. The study findings revealed that lessThan i greaterThan Phormidium formosum lessThan /i greaterThan can provide a new and rich source of L-asparaginase enzyme and this can be the primary report on L-asparaginase production lessThan i greaterThan P. formosum lessThan /i greaterThan . REHAM G. ELKOMY AND AIDA M. FARAG Marine microalgae, Asparaginase, Optimization, Immobilization 245-252